The present disclosure is related with a portable storage device suitable for confirming a memory free space.
In a typical portable storage device represented as a USB memory, SD card, or the like, a free space decreases as storing data. Therefore, checking of a free space is required, occasionally. Checking of the free space is carried out by connecting with data processing apparatus, such as PC (personal computer). In this case, a free space is displayed on the data processing apparatus side, and it is very inconvenient.
There is an external storage of a typical case that resolves such a problem. The external small recording medium contains a micro speaker and a power supply part. A residual quantity button is arranged on a surface of the external small recording medium. Also, a buzzer sound is informed from a micro speaker as corresponded to an operation of the residual quantity button.